The Number and Determinants of Nutrient Foramina Among Dry Human Femur Bones From the East African Population: A Cross-Section Study

Abstract

Background: Nutrient foramina form important landmarks on the femur and other bones as the portal of entry for nutrient arteries. Nutrient arteries are important sources of blood supply for growing bones; and their variations may be due to congenital or acquired causes. These variations are important in anatomical comparisons, orthopaedic surgical practice and forensic medicine. Aims: This study aimed at establishing the number and determinants of the nutrient foramina among dry human femur bones from the East African population. Materials and methods: This was a cross-section study of 333 dry femur bones from the East African population, at the Galloway osteological collection of Makerere University college of health sciences. The number of nutrient foramina on the shaft of each femur, the corresponding demographic, clinical and morphometric characteristics were documented. Data were entered in an Excel sheet and exported to STATA 14 for analysis. Univariate, bivariate and multivariable analyses were performed to obtain the summary statistics and the measures of association. At all levels of analysis, a p-value of less than 0.05 was considered statistically significant. Results: Of the 333 femurs, 291 (87.4%) were from males; and 137(50.15%) were right femurs. The age ranged from 20 to 75 years with a mean age of 35 (SD± 12) years. Nutrient foramina ranged from one to four; mean of 1.4 (SD±0.5) and median of 1 (IQR: 1 to 2). Of the 333 femurs, 199 (59.8%) had one foramen, 129 (38.7%) had two foramina, four femurs had three foramina and one femur had four foramina. There was a statistically significant association between the number of nutrient foramina and the femur’s: mid-shaft circumference (p=0.014; 95%CI: 0.003 to 0.028), nationality (p=0.016; 95%CI: -0.284 to -0.030) and sex (p=0.012; 96% CI: -0.405 to -0.050). Conclusion: Nutrient foramina among femurs from the East African population range from one to four per femur, with predominantly one foramen. The key determinants of the number of foramina are: mean mid-shaft circumference, nationality and sex. These findings are significant in anatomical comparisons; forensic and orthopaedic practices. KEY WORDS: Nutrient foramina, dry human femur, East African population, morphometric characteristics.